OK, so it's a vibration at about 70 mph, and is more distinct when i go to accelerate, it's not wheel balance b/c there is no pull, could it be my drive shaft. i rebuilt my engine less than 50 miles ago, but it did it b4 i rebuilt it, now it's just worse, could my u joints have gotten more messed up than they were from the transmission shifting around while trying to put the motor back in, the vibration kind of pulsates and gets worse into just a constant vibration. does this sound like my problem or am i barking up the wrong tree
i would start with a balance of the tires i have had cars that the tires were way out of balance and there was no pull.
check your u-joints. i had a lot of vibration and when i replaced the u-joints it completly went away
dont forget if your Ujoint bearing cups are not seated carefully in the yolk, between the little tabs, at the rearend the u bolts will be loose and so will the u joint causing vibration. i would check that first then check the u joints themselves if that is good. also did you replace the transmission mount with a new one? more power getting to the same old mount could easily tweak something that was just barely holding on before....
Well if the u joints are bad, it's really easy to check em out. Pull the driveshaft and move em by hand, every which way they'll move. If one's bad, you'll feel it.
i would guess that the angle that the motor and trans has changed probly due to the motor mounts being changed or the trans mount. the drive shaft angle to the diff and the trans needs to be with in 2 degrees of each other.
Do you feel the vibration more in the steering wheel, shifter or body?? Does it go away when coasting??
I Know...I Know !!! "Every repair manual I've seen said to mark the driveshaft before removal. Being installed 180* ain't going to shake the fillings out of your head unless the driveshaft is about to let go, but you will feel a slight vibration in the seat. I scanned what Chilton's, Motors and Haynes have to say about marking a driveshaft prior to removing in their big books." Attached Thumbnails ...posted by Jeff... ...Frank...:Handshake
vibration "did it before the rebuild" Existing problem, just made worse from the engine change? Probably a driveshaft/u-joint issue as already noted. Was the vibration in the steering wheel? 1- rebalance the wheels...vibration has nothing to do with a frt end pulling, thats a frt end alingment or air pressure issue. 2- replace the u-joints...they were probably due anyway. 3- Have driveshaft rebalanced with the new u-joints 4- did you move the tires around? Were any moved rt to left? If they are radials, this can sometimes cause issues, pulling and or vibrations Just some thoughts to go with all the above Let us know what you find out.
Dont forget the, as mentioned by myself and a couple others, trans mount. mine wore out and moved the rear of the transmission offline as stated earlier.Placing both mounts side by side i could see the bolts moved over on the worn one by almost an inch. when i replaced the worn mount with a good mount that eliminated the problem.
